Journal articles: 'Removal of Sulfer compound'

1

Kumar, Sunil, Vimal Chandra Srivastava, Ashutosh Kumar, and Shrikant Madhusudan Nanoti. "Effect of gas oil composition on performance parameters of the extractive desulfurization process." RSC Advances 6, no. 30 (2016): 25293–301. http://dx.doi.org/10.1039/c5ra27757d.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Yasuda, Tomoko, Miyoko Waki, Yasuyuki Fukumoto, Hiroaki Saito, and Hiroki Yokojima. "Odorous Compound Removal Performance and Water Properties of a Biotrickling Filter Installed in a Piggery." Applied Engineering in Agriculture 37, no. 4 (2021): 563–72. http://dx.doi.org/10.13031/aea.14443.

Full text

Abstract:

Highlights We evaluated the performance of a two-stage biotrickling filter in a pig facility. A short empty bed residence time lowered the secondary filter removal efficiency for many odorous compounds. The removal efficiency of some compounds increased when the pH in the secondary water tank decreased. Low-odor-threshold compounds such as MT, n-BA, n-PA, and p-cresol were indicated as targets for optimization. Abstract . Odor is a major problem in pig production, and it is important to minimize odor emissions. To determine the factors influencing variations in odor removal efficiency, we analyzed the performance of a biotrickling filter installed in growing-finishing pig rooms on a commercial farm. Over 16 months, we conducted measurements of representative odorous compounds, namely sulfur compounds (hydrogen sulfide, methanethiol, dimethyl sulfide, and dimethyl disulfide), volatile fatty acids (propanoic acid, 2-methylpropanoic acid, butanoic acid, 3-methylbutanoic acid, and pentanoic acid), and ammonia. The average removal efficiencies of methanethiol, dimethyl disulfide, volatile fatty acids, and ammonia were 83% to 89%, with 50% for hydrogen sulfide and 18% for dimethyl sulfide. For many, but not all, odorous compounds, removal efficiency declined significantly with decreasing empty bed residence time (EBRT). From an analysis of the correlations of odorous compounds’ removal efficiency with the properties of the trickling water, we hypothesized that water properties such as pH, free ammonia, free nitrous acid, ionic species (Na+, Ca2+) concentrations, temperature, electrical conductivity, and biological oxygen demand, in addition to EBRT, were associated with fluctuations in removal efficiency during full-scale operation. The pH in the secondary water tank was negatively correlated with the removal efficiencies of methanethiol, dimethyl sulfide, butanoic acid, 3-methylbutanoic acid, pentanoic acid, and ammonia. Our identification of key odorous compounds indicates the importance of the secondary filter in odor treatment. Biotrickling filters for air in pig facilities could be further optimized by targeting low-odor-threshold compounds such as methanethiol, butanoic acid, pentanoic acid, and p-cresol, in addition to ammonia. Keywords: Ammonia, Biotrickling filter, Pig facility odor, Sulfur compound, Trickling water, Volatile fatty acid.

APA, Harvard, Vancouver, ISO, and other styles

3

Kolarski, Dejan, Jelena Janković, Draginja Mihajlović, Neda Kovačević, and Jelena Lukić. "Solving the problem of exploitation of transformers with corrosive sulfur by oil desulfurization using a strong inorganic base and organic solvent." Zbornik radova Elektrotehnicki institut Nikola Tesla 31, no. 31 (2021): 113–23. http://dx.doi.org/10.5937/zeint31-34696.

Full text

Abstract:

Most power transformer failures are associated with the presence of corrosive sulfur compounds in mineral insulating oil, of which dibenzyl disulfide (DBDS) is the best known and most widespread corrosive sulfur compound. The oil of failed transformers usually contained DBDS, a compound with a pronounced affinity for the formation of copper (I) sulfide (Cu2S). Copper (I) sulfide is a compound that does not dissolve in oil, conducts electricity, and can be deposited on the paper insulation or copper conductor of the transformer. Created conductive paths between the windings can initiate turn-to-turn breakdown and failure of the transformer. Several technological procedures have been developed as a solution to oil corrosivity. The application of desulfurization technology developed by the Electrical Engineering Institute "Nikola Tesla" enables the efficient removal of DBDS and aging products from mineral insulation oils.

APA, Harvard, Vancouver, ISO, and other styles

4

Antonova, O. I., K. R. Vepryntseva, and Ye M. Komyakova. "BASIC NUTRIENT CONSUMPTION AND REMOVAL WITH RAPESEED SEEDS WHEN APPLYING DIFFERENT FERTILIZER COMBINATIONS." Vestnik Altajskogo gosudarstvennogo agrarnogo universiteta, no. 12 (December 2021): 5–11. http://dx.doi.org/10.53083/1996-4277-2021-206-12-5-11.

Full text

Abstract:

In the context of different fertilizer combination applica-tion (urea-ammonia liquor KAS-32, liquid complex fertilizer ZhKU, and compound NPK fertilizerDiammophoska) N89P26K26S14, N70P26K26S14, N73P39K13S14, N89P39K13S14, N87P37S14and N71P37S14, we revealed increased removal of CaO to 15.6-20 kg ha as opposed to 13.8 kg ha in the con-trol; MgO to 12.3-16 kg ha compared to 10.2 kg ha in the control. Taking into account Ca and Mg removal without return, it requires the introduction of compound fertilizers containing these nutrients into the fertilizer system. Nitro-gen removal was 110.3-165.5 kg ha compared to 102.6 kg ha, and sulfur -10.9-12.8 kg ha compared to 7.8 kg ha in the control. The S/N ratio ranged from 8.9-15.4 compared to 14 in the control. For the most part, it was equal to 10.7-12.9 which was indicative of satisfactory sulfur supply to oil seed rape crops and the need to increase sulfur dose to 21-28 kg ha. The largest removal of all nutrients was found inthe variants with N73P39K13S14and N71P37S14; the highest yield was formed with N73P39K13S14with N:P:K removal ratio of 1:0.39:0.21

APA, Harvard, Vancouver, ISO, and other styles

5

Li, Shun De, Ye Tong Ye, Lan Li, Guo Yu Wei, and Qing Ning Wang. "Study the Removal of Sulfide in MTBE Base on the Attapulgite Desulfurizer." Advanced Materials Research 1053 (October 2014): 208–15. http://dx.doi.org/10.4028/www.scientific.net/amr.1053.208.

Full text

Abstract:

A novel desulfurizer was prepared to remove the sulfide in MTBE. The performance of the desulfurizer was investigated by L18(2×37) Orthogonal Test. The desulfurizer for MTBE was prepared by the impregnating technique, in which the transitional metal Fe series and Ag series compounds were used as active components, and the modified attapulgite clay as the carrier. In order to get the optimum conditions to desulfurization in MTBE, IR, XRD, TEM, XPS technology were used to study the desulfurization mechanism. Compare the desulfurization characterize before and after the experiment. The result shows that the desulfurizer made by 8% Fe series compound and 2% Ag series compound, and roasted at 300°C for 3 hours. The Sulfur content in MTBE was reduced from 789mg/kg to 124mg/kg. The desulfurization rate was reached to 84.18% (in normal temperature and pressure.). The removal effect is obvious. The result of this study can be applied for Removal sulfide in MTBE.

APA, Harvard, Vancouver, ISO, and other styles

6

Shahriar, Syed, Xue Han, Hongfei Lin, and Ying Zheng. "Adsorptive Removal of Nitrogen and Sulfur Containing Compounds by SBA15 Supported Nickel (II) and Tungsten Phosphides and the Adsorption Mechanisms." International Journal of Chemical Reactor Engineering 14, no. 4 (August 1, 2016): 823–30. http://dx.doi.org/10.1515/ijcre-2015-0107.

Full text

Abstract:

Abstract SBA15 supported transition metal phosphides Ni2P/SBA15 and WP/SBA15 have been identified as promising adsorbents especially for removing neutral nitrogen-containing compounds. Adsorption of model nitrogen- and sulfur-containing compounds as well as light cycled oil (LCO) was performed and applied for the evaluation of kinetics and isotherms. The pseudo second-order kinetic model was well fitted to both nitrogen and sulfur adsorption data. Molecular size of the adsorbates plays an important role in the adsorption. Despite of higher initial adsorption rates, the adsorption capacities for carbazole and DBT were lower than those for indole and quinoline due to their larger molecular size. Monolayer adsorption was observed for quinoline due to the acid-base interaction between the basic nitrogen adsorbate and the weak acidic support. The Freundlich model was suitable in describing the adsorption of nitrogen- and sulfur-containing compounds from LCO. Cooperative adsorption took place when replacing the model compound DBT by the sulfur-containing compounds in LCO.

APA, Harvard, Vancouver, ISO, and other styles

7

Zhu, Ying, Chuan Liu, Qiao Wen Yang, Peng Fei Li, Yong Jun Sun, and Dong Yao Xu. "Study on the Promoting Effect of Additive on the Calcium-Based Sulfur-Fixing Agent." Advanced Materials Research 773 (September 2013): 634–38. http://dx.doi.org/10.4028/www.scientific.net/amr.773.634.

Full text

Abstract:

Based on the removal of SO2 as the research background, this paper focuses on the research of mono-component experiment and orthogonal experiment of compound sulfur-fixing agent composed of shell powder and red mud (at the mass ratio of 8:2) at the temperature of 1000°C and Ca/S was 2.0, by adding manganese dioxide, fly ash, magnesium oxide and potassium carbonate as the sulfur-fixing additive. The experimental results showed that the sulfur fixation capacity of desulfurizer is increased to different extents and the optimal ratio to additive is obtained after addition of the additive.

APA, Harvard, Vancouver, ISO, and other styles

8

Wang, Jing, and Rui Wang. "Characteristics of New Absorbent System of Heteropoly Compound Solution for H₂S Removal." Key Engineering Materials 531-532 (December 2012): 246–49. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.246.

Full text

Abstract:

A new liquid redox method for low sulfur containing gas treatment, with H2S concentration less than 1000mg/m3, was developed employing the heteropoly compounds of molybdenum and phosphorus by the present authors. The desulfurization characteristics of the absorbent system of vanadium substituted heteropoly acid, viz. H4PVMo11O40, were investigated by dynamic outlet-gas H2S concentration detection method. Like the aqueous solution of the parent compound, namely H3PMo12O40 or its sodium salt, H4PVMo11O40 solution can also be used as efficient absorbent for H2S removal. The absorbent system of H4PVMo11O40 solution was found to have fairly good absorption-regeneration performance, with a H2S removal rate of up to 100% in the presence of CuS as additive, hence it is promising in pollution control and resource reclamation.

APA, Harvard, Vancouver, ISO, and other styles

9

Li, Kaiyue, and Wuping Liao. "Two sulfur and nitrogen-rich cobalt–thiacalix[4]arene compounds for the selective mercury removal from aqueous solutions." CrystEngComm 22, no. 44 (2020): 7668–72. http://dx.doi.org/10.1039/d0ce01209b.

Full text

Abstract:

Two thiacalix[4]arene-based coordination compounds, a {Co₂₄} octahedral coordination cage and a {Co₈} cluster, are effective adsorbents towards Hg(ii) and the adsorption capacity of the {Co₂₄} cage compound reaches 330 mg g⁻¹.

APA, Harvard, Vancouver, ISO, and other styles

10

Luo, Wei, and Qiang Wu. "Development of wellbore compound blockage removal technology to reduce production loss in the ultra-deep and high-sulfur Yuanba gas field." Journal of Petroleum Exploration and Production Technology 10, no. 8 (September 15, 2020): 3711–21. http://dx.doi.org/10.1007/s13202-020-01000-5.

Full text

Abstract:

Abstract Wellbore compound blockage occurs in several wells of Yuanba gas field during production, which seriously affects the stable production. The prior treatment with inorganic acid injection does not show a good effect. Therefore, it is urgent to establish an effective blockage removal technology. In this work, the composition analysis of compound blockage samples is firstly carried out. Then, two types of acid solution and barite dissolvent for different types of wellbore blockage are developed. Finally, the corresponding crafts of wellbore blockage removal for different degrees of wellbore blockage are set up. Analysis results show that the inorganic components of blockages are mainly FeS2, CaCO3, BaSO4, and SiO2. The organic components of blockages are mainly the decomposition products of macromolecular materials and the asphaltene. There are differences in the components of blockages between different wells in Yuanba gas field. Some wells are the type of organic-based blockage, while others are the type of inorganic-based blockage. The field application shows that the developed wellbore compound blockage removal technology has successfully guided the in situ removal operation of eight wells in Yuanba gas field, ensuring the smooth completion of production task of this gas field. This effective blockage removal technology can be extended to similar ultra-deep and high-sulfur gas field.

APA, Harvard, Vancouver, ISO, and other styles

11

Mohd Zaid, Hayyiratul Fatimah, Chong Fai Kait, and Muhammad Ibrahim Abdul Mutalib. "Photocatalytic Oxidative Desulfurization of Model Oil Using Cu/TiO₂ Photocatalyst and Eutectic Based Ionic Liquid: Effect of Metal Loading." Applied Mechanics and Materials 699 (November 2014): 210–14. http://dx.doi.org/10.4028/www.scientific.net/amm.699.210.

Full text

Abstract:

Titanium dioxide (TiO2) photocatalyts doped with copper metal at different metal loadings were successfully prepared and characterized. Photocatalytic oxidative desulfurization of model oil containing dibenzothiophene as the sulfur compound (100 ppm) was investigated using the prepared photocatalyst. The photocatalyst with 2.0 wt% Cu metal loading showed the best sulfur removal at 66.25%.

APA, Harvard, Vancouver, ISO, and other styles

12

Nawaf, Amer Talal, Shymaa Ali Hameed, Layth T. Abdulateef, Aysar Talib Jarullah, Mohammed S. Kadhim, and Iqbal M. Mujtaba. "A Novel Synthetic Nano-Catalyst (Ag2O3/Zeolite) for High Quality of Light Naphtha by Batch Oxidative Desulfurization Reactor." Bulletin of Chemical Reaction Engineering & Catalysis 16, no. 4 (July 30, 2021): 716–32. http://dx.doi.org/10.9767/bcrec.16.4.11383.716-732.

Full text

Abstract:

Oxidative desulfurization process (ODS), enhanced with a novel metal oxide (Ag ions) as an active component over nano-zeolite that has not been reported in the literature, is used here to improve the fuel quality by removing mercaptan (as a model sulfur compound in the light naphtha). Nano-crystalline (nano-support (Nano-zeolite)) composite is prepared by Incipient Wetness Impregnation method loaded with a metal salt to obtain 0.5, 1 and 1.5% of Ag2O3 over Nano-zeolite. The new homemade nano-catalysts (Ag2O3/Nano-zeolite) prepared are characterized by Brunauer–Emmett–Teller (BET) (surface area, pore volume and pore size), X-ray Diffraction (XRD), Fourier Transform Infra Red (FTIR), and Scanning Electron Microscopy (SEM) analysis. The ODS process is then used to evaluate the performance of the catalysts for the removal of sulfur at different reaction temperatures (80–140 °C) and reaction times (30–50 min) in a batch reactor using the air as oxidant. 87.4% of sulfur removal has been achieved using 1% silver oxide loaded on Nano zeolite (1% of Ag2O3/Nano-zeolite) giving a clear indication that our newly designed catalyst is highly efficient catalyst in the removal of sulfur compound (mercaptan) from naphtha. A new mechanism of chemical reaction for sulfur removal by oxygen using the new homemade catalyst (Ag2O3/Nano-zeolite) prepared has been suggested in this study. The best kinetic model parameters of the relevant reactions are also estimated in this study using pseudo first order technique based on the experimental results. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

APA, Harvard, Vancouver, ISO, and other styles

13

Molino, Giulia, Marta Gandiglio, Sonia Fiorilli, Andrea Lanzini, Davide Drago, and Davide Papurello. "Design and Performance of an Adsorption Bed with Activated Carbons for Biogas Purification." Molecules 27, no. 22 (November 15, 2022): 7882. http://dx.doi.org/10.3390/molecules27227882.

Full text

Abstract:

Organic waste can be efficiently converted into energy using highly efficient energy systems, such as SOFCs coupled to the anaerobic digestion process. SOFC systems fed by biogenous fuels, such as biogas or syngas, suffer long-term stability due to trace compound impacts. It follows that, a mandatory gas cleaning section is needed to remove these pollutants at lower concentrations. This work investigates the adsorption mechanism for micro-contaminant removal through experimental results achieved using solid sorbents. Samples of different sorbent materials were analyzed in the laboratory to determine their performances in terms of sulfur (mainly hydrogen sulfide) and siloxanes (mainly D4-Octamethylcyclotetrasiloxane) adsorption capacities. The analysis shows that the chemical composition of the samples influences the adsorption of H2S (i.e., presence of calcium, iron, copper), while the effect of their textural properties mainly influences the adsorption of siloxane compounds, such as D4. A quantitative analysis was performed considering the influence of gas velocity on adsorption capacity. By increasing the biogas velocity (+45% and +89%), there was an indirect correlation with the H2S adsorption capacity (−27% and −44%). This identified an aspect related to the residence time required to be able to remove and retain the trace compound. The results obtained and summarized were used to develop a strategy for the removal of trace compounds in large-scale plants, e.g., for water purification.

APA, Harvard, Vancouver, ISO, and other styles

14

Ahmed, Barham Sharif, Luqman Omar Hamasalih, Kosar Hikmat Hama Aziz, Yousif M. Salih, Fryad S. Mustafa, and Khalid Mohammad Omer. "Efficient Oxidative Desulfurization of High-Sulfur Diesel via Peroxide Oxidation Using Citric, Pimelic, and α-Ketoglutaric Acids." Separations 10, no. 3 (March 15, 2023): 206. http://dx.doi.org/10.3390/separations10030206.

Full text

Abstract:

The widespread use of diesel fuel for transportation, industry, and electricity generation causes several environmental issues via an increase in the amount of sulfur compound emissions. Commercial diesel fuel must be free of sulfur-containing compounds since they can cause several environmental problems. Considering the currently available processes to eliminate sulfur compounds, oxidative desulfurization (ODS) is one of the effective means for this purpose. This work presented a simple, low cost, and efficient ODS system of high-sulfur diesel fuels using peroxide oxidation with the aid of citric, pimelic, and α-ketoglutaric acids. The aim of the study was to investigate the potential of these acids as hydrogen peroxide (H2O2) activators for ODS and to optimize the reaction conditions for maximum sulfur removal. The results showed that citric, pimelic, and α-ketoglutaric acids were effective catalysts for the desulfurization of high-sulfur diesel with an initial sulfur content of 2568 mg L−1, achieving a sulfur removal efficiency of up to 95%. The optimized reaction conditions were found to be 0.6 g of carboxylic acid dosage and 10 mL of H2O2 at 95 °C. The desulfurization efficiency of the real diesel sample (2568 mg L−1) was shown to be 27, 34, and 84.57%, using citric acid, α-ketoglutaric acid, and pimelic acid after 1h, respectively. The effectiveness of the oxidation process was characterized by gas chromatographic pulsed flame photometric detector (GC-PFPD) and Fourier-transform infrared spectroscopy (FTIR) techniques. The experimental results demonstrated that the developed system exhibited high efficiency for desulfurization of real high-sulfur diesel fuels that could be a good alternative for commercial application with a promising desulfurization efficiency.

APA, Harvard, Vancouver, ISO, and other styles

15

Silva, Dinis F., Alexandre M. Viana, Isabel Santos-Vieira, Salete S. Balula, and Luís Cunha-Silva. "Ionic Liquid-Based Polyoxometalate Incorporated at ZIF-8: A Sustainable Catalyst to Combine Desulfurization and Denitrogenation Processes." Molecules 27, no. 5 (March 5, 2022): 1711. http://dx.doi.org/10.3390/molecules27051711.

Full text

Abstract:

An effective and sustainable process capable of simultaneously execute desulfurization and denitrogenation of fuels is in fact an actual necessity in the refinery industry. The key to achieve this goal is the parallel oxidation of sulfur and nitrogen compounds present in fuels, which is only achieved by an active and recovered catalyst. A novel heterogeneous catalyst was successfully prepared by the encapsulation of an imidazolium-based polyoxometalate (POM) into a ZIF-8 framework ([BMIM]PMo12@ZIF-8). This composite material revealed exceptional catalytic efficiency to concurrently proceed with the oxidative desulfurization and denitrogenation of a multicomponent model fuel containing various sulfur and nitrogen compounds. A complete removal of all these compounds was achieved after only one hour and the catalyst system was able to be reused for ten consecutive cycles without loss of efficiency. In fact, an ionic liquid POM was incorporated in the ZIF-8 for the first time, and this composite compound was originally applied as a catalyst for simultaneous oxidative desulfurization and denitrogenation processes.

APA, Harvard, Vancouver, ISO, and other styles

16

Mohammed, Wadood Taher, Raghad Fareed Kassim Almilly, and Sheam Bahjat Abdulkareem Al-Ali. "Desulfurization of Diesel Fuel by Oxidation and Solvent Extraction." Journal of Engineering 21, no. 2 (February 1, 2015): 87–102. http://dx.doi.org/10.31026/j.eng.2015.02.06.

Full text

Abstract:

This research presents a study in ultra-desulfurization of diesel fuel produced from conventional hydro desulfurization process, using oxidation and solvent extraction techniques. Dibenzothiophene (DBT) was the organosulfur compound that had been detected in sulfur removal. The oxidation process used hydrogen peroxide as an oxidant and acetic acid as homogeneous catalyst . The solvent extraction process used acetonitrile (ACN) and N-methyl – 2 - pyrrolidone (NMP) as extractants . Also the effect of five parameters (stirring speed :150 , 250 , 350 , and 450) rpm, temperature (30 , 40 , 45 , and 50) oC, oxidant/simulated diesel fuel ratio (0.5 , 0.75 , 1 , and 1.5) , catalyst/oxidant ratio(0.125,0.25,0.5,and0.75) , and solvent/simulated diesel fuel ratio(0.5,0.6,0.75,and1) were examined as well as solvent type. The results exhibit that the highest removal of sulfur is 98.5% using NMP solvent while it is 95.8% for ACN solvent. The set of conditions that show the highest sulfur removal is: stirring speed of 350 rpm , temperature 50oC , oxidant/simulated diesel fuel ratio 1 , catalyst/oxidant ratio 0.5 , solvent/simulated diesel fuel ratio 1. These best conditions were applied upon real diesel fuel (produced from Al-Dora refinery)with 1000 ppm sulfur content . It was found that sulfur removal was 64.4% using ACN solvent and 75% using NMP solvent.

APA, Harvard, Vancouver, ISO, and other styles

17

Praveen, Reddy P., and Rao V. Uma Maheswara. "Effect of nutrient and physical parameters on dibenzothiophene desulfurization activity of Streptomyces sp. VUR PPR 101 isolated from oil contaminated soils of mechanical workshops." Research Journal of Chemistry and Environment 26, no. 6 (May 25, 2022): 86–99. http://dx.doi.org/10.25303/2606rjce086099.

Full text

Abstract:

Motor vehicles use petroleum products and release sulfur dioxide gas which causes deleterious effects to environment and humans. The sulfur containing compounds present in petroleum products especially organosulfur compounds serve as major source of sulfur dioxide emission. During refining process, petroleum products are subjected to hydrodesulfurization for the removal of sulfur, which is not an efficient method and most of the organosulfur compounds are not eliminated particularly dibenzothiophene and its derivatives. A process known as biodesulfurization which employs microorganisms was suggested to be an alternative to hydrodesulfurization. The dibenzothiophene was selected as model organosulfur compound to perform biodesulfurization studies due its high recalcitrant nature. The microbes which remove sulfur via 4S pathway from organosulfur compounds (dibenzothiophene) are commercially important. In the present study, the effect of different nutrient sources (carbon, nitrogen and amino acid sources at different concentrations) and physical parameters like temperature and pH on dibenzothiophene desulfurization activity (via 4S pathway) of Streptomyces sp. VUR PPR 101 was studied and optimized. The optimum carbon and nitrogen sources for DBT biodesulfurization activity were found to be 4% glucose and 1% yeast extract, respectively. The best amino acid source reported was 0.3 mg/ml glutamine. At a temperature of 300C and pH 7.0, the organism showed maximum biodedulfurization activity.

APA, Harvard, Vancouver, ISO, and other styles

18

Mohd Zaid, Hayyiratul Fatimah, Chong Fai Kait, and Mohamed Ibrahim Abdul Mutalib. "Photo Oxidative Extractive Desulfurization of Model Oil Using Fe/TiO₂ Photocatalyst and Eutectic Based Ionic Liquid: Effect of Metal Loading." Advanced Materials Research 1133 (January 2016): 664–68. http://dx.doi.org/10.4028/www.scientific.net/amr.1133.664.

Full text

Abstract:

Titanium dioxide (TiO2) photocatalyts doped with iron metal at different metal loadings were successfully prepared and characterized. The doped photocatalyst were characterized using diffuse reflectance spectroscopy (DR-UV-Vis), X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM).Photooxidative extractive desulfurization of model oil containing dibenzothiophene as the sulfur compound (100ppm) was investigated using the prepared photocatalyst. The photocatalyst with 0.20 wt% Fe metal loading showed the best sulfur removal at 61.13%.

APA, Harvard, Vancouver, ISO, and other styles

19

Tang, Longfei, Kuanyan Long, Songjiang Chen, Dongjiao Gui, Changying He, Jingchao Li, and Xiuxiang Tao. "Removal of thiophene sulfur model compound for coal by microwave with peroxyacetic acid." Fuel 272 (July 2020): 117748. http://dx.doi.org/10.1016/j.fuel.2020.117748.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Wu, Le, Yuqi Wang, Lan Zheng, and Xiaolong Han. "Stepwise optimization of hydrogen network integrated sulfur compound removal kinetics and a fluid catalytic cracker." Chemical Engineering Research and Design 151 (November 2019): 168–78. http://dx.doi.org/10.1016/j.cherd.2019.09.012.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Rychlewska, Katarzyna, Krystyna Konieczny, and Michał Bodzek. "Pervaporative desulfurization of gasoline – separation of thiophene/n-heptane mixture / Perwaporacyjne odsiarczanie benzyny – separacja mieszanin tiofen/n-heptan." Archives of Environmental Protection 41, no. 2 (June 1, 2015): 3–11. http://dx.doi.org/10.1515/aep-2015-0013.

Full text

Abstract:

Abstract This paper presents the recent advances in pervaporative reduction of sulfur content in gasoline. Methods of preliminary selection of membrane active layer material are presented. Interactions between gasoline components (typical hydrocarbon and sulfur species) and membranes are showed. Influence of pervaporation process parameters i.e. feed temperature, downstream pressure and feed flow rate on the separation efficiency is discussed. Investigations of the influence of sulfur concentration in fluid catalytic cracking (FCC) gasoline on membrane performance have been conducted. A series of PV tests was carried out to investigate the separation properties of the commercial composite membrane with an active layer made of poly(dimethylsiloxane) and to determine the efficiency of organic sulphur compound (thiophene) removal from model thiophene/n-heptane mixture depending on its concentration.

APA, Harvard, Vancouver, ISO, and other styles

22

Du, Zhe Hua. "Experimental Study on Catalytic Reduction of SO₂ by Rare Earth Compound." Advanced Materials Research 955-959 (June 2014): 2173–76. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.2173.

Full text

Abstract:

Compared with a great deal of traditional desulphurization crafts, the catalytic reduction of SO2 with CO to elemental sulfur is considered to be the best technology for the removal of SO2 from flue gas. Adding rare earth oxide CeO2 with variable valences to La2O3 formed a mixture of rare earth oxides. By means of dipping CeO2, La2O3 and their mixture, whose carriers are allγ-Al2O3, are used as the catalyst for the reduction of SO2 by CO. The activation process of this catalyst without O2 was investigated. The result shows that the rare earth oxide mixture composing of CeO2 and La2O3, as the catalyst for the reduction of SO2 by CO, can remove SO2 mostly without O2.

APA, Harvard, Vancouver, ISO, and other styles

23

Wang, Rui. "Investigation on a new liquid redox method for H2S removal and sulfur recovery with heteropoly compound." Separation and Purification Technology 31, no. 1 (April 2003): 111–21. http://dx.doi.org/10.1016/s1383-5866(02)00153-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Blanco-Brieva, G., J. M. Campos-Martin, S. M. Al-Zahrani, and J. L. G. Fierro. "Effectiveness of metal–organic frameworks for removal of refractory organo-sulfur compound present in liquid fuels." Fuel 90, no. 1 (January 2011): 190–97. http://dx.doi.org/10.1016/j.fuel.2010.08.008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Ling, Min Yan, and Hou He Chen. "Oxidation Chlorination of Thiophene in Coking Benzene." Applied Mechanics and Materials 130-134 (October 2011): 1066–69. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.1066.

Full text

Abstract:

Thiophene is a typical thiophenenic sulfur compound that exists in coking benzene. In this paper, investigate oxidation chlorination of thiophene in coking benzene. Potassium permanganate was combined with hydrochloric acid for a new KMnO4/HCl system of oxidation desulfurization. The preliminary results show that the thiophene in the benzene cannot be deep oxidized desulfurization alone potassium permanganate solution even at acetum. The thiophene in the coking benzene could be mostly converted by using KMnO4/HCl system. In suitable reaction conditions thiophene’s removal rate can reach more than 93%.

APA, Harvard, Vancouver, ISO, and other styles

26

Wang, Rui. "Investigation of Hydrogen Sulfide Removal and Sulfur Recovery from Low Sulfur Containing Gases with Aqueous Solution of Heteropoly Compound." JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 35, no. 1 (2002): 15–21. http://dx.doi.org/10.1252/jcej.35.15.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Zhang, Guijiao, Tianfeng Gu, Yongchao Zhou, David Z. Zhu, and Yiping Zhang. "Effects of intermittent chemical dosing on volatile sulfur compounds in sewer headspace." Environmental Engineering Research 27, no. 3 (April 25, 2021): 210091–0. http://dx.doi.org/10.4491/eer.2021.091.

Full text

Abstract:

Volatile sulfur compounds (VSCs), including hydrogen sulfide (H2S) and volatile organic sulfide compounds (VOSCs), can be produced in sewer systems causing sewer odor problems. In this study, the effects of intermittently dosing ferric iron, hydrogen peroxide, and nitrate on H2S and VOSCs in sewer headspace were investigated. In order to characterize the composition of VSCs, an HC-3 trace sulfur analyzer and gas chromatograph (GC) equipped with a triple quadrupole-type mass spectrometry (MS) apparatus were used to determine the VSCs. The results indicated that the effect of intermittent addition of 40 mg/L ferric iron or 40 mg/L hydrogen peroxide is limited for VSCs inhibition. The H2S and VOSCs concentrations increased significantly in the late-stage experiments, even around 20% and 30% respectively higher than the initial average concentrations. However, the intermittent addition of 40 mg N/L nitrate has a relatively stable control effect of H2S and VOSCs which maintaining 60% removal rate. Moreover, methyl mercaptan (MeSH) was the most abundant compound of the total VOSCs released and the results of the theoretical odor concentration study also indicate MeSH is the main VOSC causing the significant odor problem. Therefore, more attention should be focused on the VOSCs which have extremely low odor threshold.

APA, Harvard, Vancouver, ISO, and other styles

28

Chen, Han, Zhipeng Huang, Juping You, Yinfeng Xia, Jiexu Ye, Jingkai Zhao, and Shihan Zhang. "Dibenzothiophene Removal from Fuel Oil by Metal-Organic Frameworks: Performance and Kinetics." International Journal of Environmental Research and Public Health 20, no. 2 (January 6, 2023): 1028. http://dx.doi.org/10.3390/ijerph20021028.

Full text

Abstract:

Desulfurization of organic sulfur in the fuel oil is essential to cut down the emission of sulfur dioxide, which is a major precursor of the acid rain and PM2.5. Currently, hydrodesulfurization is regarded as a state-of-art technology for the desulfurization of fuel oil. However, due to the stringent legislation of the fuel oil, the deep desulfurization technology is urgent to be developed. Adsorptive desulfurization method is promising due to the high selectivity and easy operation. The development of efficient adsorbent is important to advance this technology into industrial application. In this work, the five types of metal-organic frameworks (MOFs), including Cu-BTC, UMCM-150, MIL-101(Cr), UIO-66, and Cu-ABTC were synthesized for the adsorption of dibenzothiophene (DBT), a typical organic sulfur compound in the fuel oil. The experimental results revealed that the adsorption capacity of the five MOFs followed the order of Cu-ABTC, UMCM-150, Cu-BTC, MIL-101(Cr), and UIO-66, which adsorption capacities were 46.2, 34.2, 28.3, 26.3, and 22.0 mgS/g, respectively. The three types of Cu-based MOFs such as Cu-ABTC, UMCM-150, and Cu-BTC outperformed the Cr-based MOFs, MIL-101, and Zr-based MOFs, UIO-66. Since the surface area and pore volumes of the Cu-based MOFs were not the greatest among the tested five MOFs, the physical properties of the MOFs were not the only limited factor for the DBT adsorption. The π-complexation between DBT and linkers/metal in the MOFs was also important. Kinetic analysis showed that the DBT adsorption onto the five tested MOFs follows the pseudo-second-order kinetics, confirming that the chemical π-complexation was also contributed to the DBT adsorption. Furthermore, the operation parameters such as oil-adsorbent ratio, initial sulfur concentration and adsorption temperature for the DBT adsorption onto Cu-ABTC were optimized to be 100:1 g/g, 1000 mgS/L and 30 °C, respectively. This work can provide some insights into the development of efficient adsorbent for the organic sulfur adsorption.

APA, Harvard, Vancouver, ISO, and other styles

29

Le Borgne and Baquerizo. "Microbial Ecology of Biofiltration Units Used for the Desulfurization of Biogas." ChemEngineering 3, no. 3 (August 7, 2019): 72. http://dx.doi.org/10.3390/chemengineering3030072.

Full text

Abstract:

Bacterial communities’ composition, activity and robustness determines the effectiveness of biofiltration units for the desulfurization of biogas. It is therefore important to get a better understanding of the bacterial communities that coexist in biofiltration units under different operational conditions for the removal of H2S, the main reduced sulfur compound to eliminate in biogas. This review presents the main characteristics of sulfur-oxidizing chemotrophic bacteria that are the base of the biological transformation of H2S to innocuous products in biofilters. A survey of the existing biofiltration technologies in relation to H2S elimination is then presented followed by a review of the microbial ecology studies performed to date on biotrickling filter units for the treatment of H2S in biogas under aerobic and anoxic conditions.

APA, Harvard, Vancouver, ISO, and other styles

30

Yokogawa, Yoshiyuki, Shota Namba, Hiroya Sano, Shota Namba, Kazuo Fujii, Yuki Morita, M. Hotta, and Yutaka Doi. "VSC Adsorption Capability of Layered Double Hydroxide Containing Iron." Journal of Biomimetics, Biomaterials and Biomedical Engineering 26 (February 2016): 93–96. http://dx.doi.org/10.4028/www.scientific.net/jbbbe.26.93.

Full text

Abstract:

Most etiology of bad breath is often concerned with gram-negative anaerobic bacteri, and pharmacotherpy using pharmaceutical drugs should be effective but limited, because bacteria at deep periodontal pocket may be sterilized but cannot be washed out and the malodorous compounds remain. The absorbents for the malodorous compound such as volatile sulfur compounds (VSC), hydrogen sulfide (H2S), are expected to prevent the teeth from decaying and peiodontics disease. The VSC adsorption capabilities of layered double hydroxides, of which composition is A1-xBx(OH)2Cx/n·mH2O, where A and B are Mg and Fe ions, and C are carbonate (CO32- : MgFe HTCO3) and chlorine (Cl - : MgFe HTCl) ions in aqueous medium was studied by GC/FPD. The concentration of H2S rapidly decrease to less than 15% for first 1 hours of soaking in H2S water and fell to 0% in 4-5 h when the MgFe HTCO3 and MgFe HTCl were used. The iron ion was not detected in the H2S water after soaking for 18 hours.The MgFe HTCO3 and MgFe HTCl are expected to be likely adsorbent for the fast removal of VSC from the mouth.

APA, Harvard, Vancouver, ISO, and other styles

31

Świetlicka, Aleksandra, Agnieszka Środa, Violetta Kozik, Andrzej Bąk, Krzysztof Barbusiński, Natalia Howaniec, and Adam Smoliński. "Electrochemical Corrosion Monitoring in Low Conductive Fluid: Pilot-Scale Study on Sulfolane Corrosion Potential." Proceedings 16, no. 1 (June 12, 2019): 5. http://dx.doi.org/10.3390/proceedings2019016005.

Full text

Abstract:

Solvents are a group of chemical compounds that are widely used in organic synthesis. Taking into account the chemical nature, solvents are divided into protic and aprotic ones. An attractive alternative to commonly used industrial extractive liquids is an anthropogenic, organosulfur medium—sulfolane. Sulfolane is a five-membered heterocyclic sulfur–organic compound from the group of sulfones (R-SO2-R’, where R/R’ is alkyl, alkenyl, or aryl), which contains an apolar hydrocarbon backbone and a polar functional group. It is a selective solvent in the liquid–liquid and liquid–vapor extraction processes used for the removal of close-boiling alkanes from cycloalkanes or for the separation of compounds with different degrees of saturation and polarity in the extractive rectification of arenes from non-aromatic saturated hydrocarbon mixtures. In standard conditions sulfolane is not an aggressive solvent for steel, but at higher temperature (170–180 °C) and oxygen availability, it may be decomposed and subsequently some corrosive (by-)products can be formed. The primary purpose of the presented pilot-case examination was to verify applicability of the industrial, multi-electrochemical technique for reliable detection of the corrosion processes in low conductive fluids.

APA, Harvard, Vancouver, ISO, and other styles

32

Hernández-Fernández, Joaquín, Heidi Cano, and Miguel Aldas. "Impact of Traces of Hydrogen Sulfide on the Efficiency of Ziegler–Natta Catalyst on the Final Properties of Polypropylene." Polymers 14, no. 18 (September 19, 2022): 3910. http://dx.doi.org/10.3390/polym14183910.

Full text

Abstract:

Sulfur compounds are removed from propylene through purification processes. However, these processes are not 100% effective, so low concentrations of compounds such as H2S may be present in polymer-grade propylene. This article studies the effects of H2S content on polypropylene polymerization through the controlled dosage of this compound with concentrations between 0.07 and 5 ppm and its monitoring during the process to determine possible reaction mechanisms and evaluate variations in properties of the material by TGA, FTIR, MFI, and XDR analysis. It was found that the fluidity index increases directly proportional to the concentration of H2S. In addition, the thermo-oxidative degradation is explained by means of the proposed reaction mechanisms of the active center of the Ziegler–Natta catalyst with the H2S molecule and the formation of substances with functional groups such as alcohol, ketones, aldehydes, CO, and CO2 by the oxidation of radical complexes. This study shows for the first time a reaction mechanism between the active center formed for polymerization and H2S, in addition to showing how trace impurities in the raw materials can affect the process, highlighting the importance of optimizing the processes of removal and purification of polymer-grade materials.

APA, Harvard, Vancouver, ISO, and other styles

33

Ismail, M., M. G. Mahmud, H. R. Ahmmed, M. S. Islam, and K. Kirtania. "Waste Tyre Pyrolysis Oil: Production, Sulfur Removal and Fractionation for Value Added Products." Journal of Science and Technology Research 4, no. 1 (July 3, 2023): 59–70. http://dx.doi.org/10.3329/jscitr.v4i1.67369.

Full text

Abstract:

Scrap tyres, one of the most common solid wastes, are increasing with the increase of vehicles number all over the world. Gradual depletion of fossil fuel requires a rapid shift towards alternative fuel sources including wastes. Globally, a lot of pyrolysis oil is generated from the management of waste tyres. The product Tyre pyrolysis Oil (TPO) has a parametric effect on the temperature, feed size, and reaction or pyrolysis time. This study explores the conditions for optimum pyrolytic oil yield (42% wt.) which was 500 ºC for 50 minutes, with a sample size of 4 cm3. The obtained TPO were fractionated at various temperature ranges using a distillation column. The fuel characteristics of TPO, e.g., viscosity, flash point, pour point, calorific value, density, carbon residue are almost similar to that of the conventional oil standards but it cannot directly be used in the combustion process due to its higher sulfur content. For the removal of the sulfur compound, a various concentration ratio (10, 15, 20, 25, 30 percentages) of a mixture of H2O2 and HCOOH (2:1) solution (maintaining a pH of 4) were mixed with TPO. A maximum of 64.52% sulfur was removed from the TPO by using 25% of H2O2 + HCOOH solution and the pyrolysis gas was passed through the Ca(OH)2 solution for wet scrubbing of SO2, CO2 and water vapor. The fractionated TPO (based on temperature range) provides valuable products e.g., bio-gasoline, biodiesel and other desirable chemicals. The production and eco-friendly use of TPO and its fractionated products can mitigate the disposal problem of waste tyre and help the eco-system to attain a sustainable environment. J. of Sci. and Tech. Res. 4(1): 59-70, 2022

APA, Harvard, Vancouver, ISO, and other styles

34

Li, Wei, Xiao Liang, Jianguo Lin, Binxia Cao, Ping Guo, Xinyi Liu, and Zhen Wang. "Sulfate reduction and mixotrophic sulfide-utilization denitrification integrated biofilm process for sulfate-laden wastewater treatment and sulfur recovery." Water Science and Technology 71, no. 12 (April 8, 2015): 1852–58. http://dx.doi.org/10.2166/wst.2015.162.

Full text

Abstract:

A novel and integrated biofilm process – the sulfate reduction (SR) and mixotrophic (MR) sulfide-utilization denitrification process (SMSD) – was recently proposed for sulfate treatment and sulfur recovery. The process consisted of two bioreactors: a 5.1 L anaerobic upflow reactor for SR, and a 3.5 L anaerobic upflow reactor for MR desulfurization–denitrification. The experiment was conducted for 370 days to evaluate the performance of SMSD at various sulfate concentrations and hydraulic retention times. The process successfully achieved sulfate, organics and nitrogen compound removal efficiencies of 94.1, 97.7 and 99.1%, respectively. Sulfate was predominantly converted to element sulfur, while nitrate and nitrite were finally converted to nitrogen gas. In SR, with the help of high pH and sponge cubes with various bacteria, 97.5% of sulfide conversion efficiency and 540 mgS/L of sulfide were obtained. In MR, sulfide was removed up to 100% and was partially oxidized to sulfur. The extent of heterotrophic denitrification, which ranged from 35.8 to 59.8%, depended on the categories of electron acceptors.

APA, Harvard, Vancouver, ISO, and other styles

35

Prasoulas, George, Konstantinos Dimos, Panayiotis Glekas, Styliani Kalantzi, Stamatis Sarris, Chrysovalantis Templis, Konstantinos Vavitsas, et al. "Biodesulfurization of Dibenzothiophene and Its Alkylated Derivatives in a Two-Phase Bubble Column Bioreactor by Resting Cells of Rhodococcus erythropolis IGTS8." Processes 9, no. 11 (November 18, 2021): 2064. http://dx.doi.org/10.3390/pr9112064.

Full text

Abstract:

Biodesulfurization (BDS) is considered a complementary technology to the traditional hydrodesulfurization treatment for the removal of recalcitrant sulfur compounds from petroleum products. BDS was investigated in a bubble column bioreactor using two-phase media. The effects of various process parameters, such as biocatalyst age and concentration, organic fraction percentage (OFP), and type of sulfur compound—namely, dibenzothiophene (DBT), 4-methyldibenzothiophene (4-MDBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), and 4,6-diethyldibenzothiophene (4,6-DEDBT)—were evaluated, using resting cells of Rhodococcus erythropolis IGTS8. Cells derived from the beginning of the exponential growth phase of the bacterium exhibited the highest biodesulfurization efficiency and rate. The biocatalyst performed better in an OFP of 50% v/v. The extent of DBT desulfurization was dependent on cell concentration, with the desulfurization rate reaching its maximum at intermediate cell concentrations. A new semi-empirical model for the biphasic BDS was developed, based on the overall Michaelis-Menten kinetics and taking into consideration the deactivation of the biocatalyst over time, as well as the underlying mass transfer phenomena. The model fitted experimental data on DBT consumption and 2-hydroxibyphenyl (2-HBP) accumulation in the organic phase for various initial DBT concentrations and different organosulfur compounds. For constant OFP and biocatalyst concentration, the most important parameter that affects BDS efficiency seems to be biocatalyst deactivation, while the phenomenon is controlled by the affinities of biodesulfurizing enzymes for the different organosulfur compounds. Thus, desulfurization efficiency decreased with increasing initial DBT concentration, and in inverse proportion to increases in the carbon number of alkyl substituent groups.

APA, Harvard, Vancouver, ISO, and other styles

36

Adhami, Forogh, Nasim Nabilzadeh, Franziska Emmerling, Mina Ghiasi, and Majid Heravi. "Synthesis of thiadiazolobenzamide via cyclization of thioxothiourea and its Ni and Pd complexes." Journal of the Serbian Chemical Society 77, no. 9 (2012): 1211–22. http://dx.doi.org/10.2298/jsc110911052a.

Full text

Abstract:

In this study, the new compound, N-(3-methyl-4- oxo[1,3,4]thiadiazolo[2,3-c][1,2,4]triazin-7-yl) benzamide, could be obtained via two different reactions: 1) reaction of 4-amino-6-Methyl-3- (Methylsulfanyl)-1,2,4-triazin-5-one with benzoyl isothiocyanate under removal of methylmercaptane, 2) reaction of 4-amino-6-Methyl-3-thioxo- 1,2,4-triazin-5-one with benzoyl isothiocyanate under elimination of hydrogen sulfide. In both reactions a new bond between sulfur and nitrogen atoms was formed and a five-membered ring was created. The oxo thiadiazolo benzamide was characterized by IR-, 1HNMR- and 13CNMR spectroscopy as well as by Mass spectrometry. X-ray crystallography was used to shed light on the structure of this new compound. Two new complexes could be generated by coordination of oxo thiadiazolo benzamide to Pd(II) and Ni(II) ions. These complexes have been analyzed by IR-, 1HNMR- and 13CNMR spectroscopy, conductometry and Thermal gravimetry (TGA). Theoretical QM Calculation GIAO has also been applied to predict the structure of the Pd complex.

APA, Harvard, Vancouver, ISO, and other styles

37

Jankovic, Jelena, Jelena Lukic, Dejan Kolarski, Djordje Veljović, Željko Radovanović, and Silvana Dimitrijević. "Isotherm, Thermodynamic and Kinetic Studies of Elemental Sulfur Removal from Mineral Insulating Oils Using Highly Selective Adsorbent." Materials 16, no. 9 (May 4, 2023): 3522. http://dx.doi.org/10.3390/ma16093522.

Full text

Abstract:

Elemental sulfur (S8) is a corrosive sulfur compound which was found to be extremely reactive to silver, causing intensive silver sulfide (Ag2S) deposition on on-load tap changer (OLTC) contacts in power transformers. A highly selective adsorbent (HSA), called Tesla’Ssorb, for the removal of S8 from mineral insulating oils was prepared from raw material (RM) using the novel procedure. In this study, the adsorption properties of HSA for the removal of S8 from the oil were determined. RM and HSA were characterized using various techniques, such as field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), and X-ray diffraction (XRD). The performance of HSA was determined by adsorption equilibrium, thermodynamic, and kinetic study through batch experiments, at various temperatures and initial concentrations of S8. The obtained results were analyzed by Langmuir and Freundlich adsorption isotherms and it was found that equilibrium data were fitted better with the Langmuir isotherm model. The maximum adsorption capacity was 4.84 mg of S8/g of HSA at 353 K. Thermodynamic parameters, such as enthalpy (ΔH°), Gibbs free energy (ΔG°), and entropy (ΔS°), were calculated and it was found that the sorption process was spontaneous (ΔG° < 0) and endothermic in nature (ΔH° > 0). It was found that the adsorption of S8 follows pseudo-second-order kinetic model, and the activation energy indicated the activated chemisorption process.

APA, Harvard, Vancouver, ISO, and other styles

38

DERIKVAND, PEYMAN, ZAHRA ETEMADIFAR, and HOSSEIN SABER. "Sulfur Removal from Dibenzothiopheneby Newly Isolated Paenibacillusvalidus Strain PD2 and Process Optimizationin Aqueous and Biphasic (Model-Oil) Systems." Polish Journal of Microbiology 64, no. 1 (2015): 47–54. http://dx.doi.org/10.33073/pjm-2015-006.

Full text

Abstract:

Dibenzothiophene (DBT) is an organic sulfur compound which remains in oil after hydrodesulfurization (HDS) process and can be removed by biodesulfurization (BDS). A new strain of Paenibacillus validus (strain PD2) was isolated from oil contaminated soils that is able to desulfurize DBT. HPLC analysis and Gibbs assay showed that this strain was capable to convert DBT to 2-Hydroxybiphenyl (2-HBP) as final product. The presence of dszC gene confirmed that DBT desulfurization occurred through the 4S pathway. Maximum growth and the highest induction in dsz operon obtained in the presence of dimethyl sulfoxide (DMSO) as sole sulfur source. DBT concentration, temperature and pH were optimized statistically for growing and resting cells by using Response Surface Methodology (RSM). All parameters in growing cells had a significant effect on 2-HBP production during BDS of DBT by P. validus PD2, although in resting cells temperature in range of 20-40 degrees C was not a significant factor. Maximum BDS for growing cells was obtained at 0.41 mM DBT concentration, pH 6.92 and temperature 31.23 degrees C. For resting cells, optimum pH, temperature and DBT concentration were 6.62, 27.73 degrees C and 7.86 mM respectively. The results of this study showed that high concentrations of DBT could be desulfurized by P. validus strain PD2 in model-oil. Thus, the isolated strain could be introduced as a proper candidate for biodesulfurization of organic sulfur in the oil industry.

APA, Harvard, Vancouver, ISO, and other styles

39

José da Silva, Márcio, and Lidiane Faria dos Santos. "Novel Oxidative Desulfurization of a Model Fuel with H2O2 Catalyzed by AlPMo12O40 under Phase Transfer Catalyst-Free Conditions." Journal of Applied Chemistry 2013 (June 12, 2013): 1–7. http://dx.doi.org/10.1155/2013/147945.

Full text

Abstract:

A novel process was developed for oxidative desulfurization (ODS) in the absence of a phase transfer catalyst (PTC) using only Keggin heteropolyacids and their aluminum salts as catalysts. Reactions were performed in biphasic mixtures of isooctane/acetonitrile, with dibenzothiophene (DBT) as a model sulfur compound and hydrogen peroxide as the oxidant. Remarkably, only the AlPMo12O40-catalyzed reactions resulted in complete oxidation of DBT into DBT sulfone, which was totally extracted by acetonitrile, reducing the sulfur content of isooctane from the 1000 ppm to <1 ppm. Ranking of catalyst efficiency is as follows: AlPMo12O40 > H3PMo12O40 > AlPW12O40 > H3PW12O40. The absence of a PTC, acidic organic peroxides, and the use of hydrogen peroxide, an environmentally benign oxidant, make up the positive aspects of AlPMo12O40-catalyzed ODS reactions. In these reactions, high rates of DBT removal (ca. 100%) were achieved within a short time (ca. 2 hours) and under mild reaction conditions.

APA, Harvard, Vancouver, ISO, and other styles

40

Lang, Yue, Yanan Yu, Hongtao Zou, Jiexu Ye, and Shihan Zhang. "Performance and Mechanisms of Sulfidated Nanoscale Zero-Valent Iron Materials for Toxic TCE Removal from the Groundwater." International Journal of Environmental Research and Public Health 19, no. 10 (May 22, 2022): 6299. http://dx.doi.org/10.3390/ijerph19106299.

Full text

Abstract:

Trichloroethylene (TCE) is one of the most widely distributed pollutants in groundwater and poses serious risks to the environment and human health. In this study, sulfidated nanoscale zero-valent iron (S-nZVI) materials with different Fe/S molar ratios were synthesized by one-step methods. These materials degraded TCE in groundwater and followed a pathway that did not involve the production of toxic byproducts such as dichloroethenes (DCEs) and vinyl chloride (VC). The effects of sulfur content on TCE dechlorination by S-nZVI were thoroughly investigated in terms of TCE-removal efficiency, H2 evolution, and reaction rate. X-ray diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) characterizations confirmed Fe(0) levels in S-nZVI were larger than for zero-valent iron (nZVI). An Fe/S molar ratio of 10 provided the highest TCE-removal efficiencies. Compared with nZVI, the 24-h TCE removal efficiencies of S-nZVI (Fe/S = 10) increased from 30.2% to 92.6%, and the Fe(0) consumed during a side-reaction of H2 evolution dropped from 77.0% to 12.8%. This indicated the incorporation of sulfur effectively inhibited H2 evolution and allowed more Fe(0) to react with TCE. Moreover, the pseudo-first-order kinetic rate constants of S-nZVI materials increased by up to 485% compared to nZVI. In addition, a TCE degradation was proposed based on the variation of detected degradation products. Noting that acetylene, ethylene, and ethane were detected rather than DCEs and VC confirmed that TCE degradation followed β-elimination with acetylene as the intermediate. These results demonstrated that sulfide modification significantly enhanced nZVI performance for TCE degradation, minimized toxic-byproduct formation, and mitigated health risks. This work provides some insight into the remediation of chlorinated-organic-compound-contaminated groundwater and protection from secondary pollution during remediation by adjusting the degradation pathway.

APA, Harvard, Vancouver, ISO, and other styles

41

Mishra, Sanjeet, Jeevan Jyot, Ramesh C. Kuhad, and Banwari Lal. "Evaluation of Inoculum Addition To Stimulate In Situ Bioremediation of Oily-Sludge-Contaminated Soil." Applied and Environmental Microbiology 67, no. 4 (April 1, 2001): 1675–81. http://dx.doi.org/10.1128/aem.67.4.1675-1681.2001.

Full text

Abstract:

ABSTRACT A full-scale study evaluating an inoculum addition to stimulate in situ bioremediation of oily-sludge-contaminated soil was conducted at an oil refinery where the indigenous population of hydrocarbon-degrading bacteria in the soil was very low (103 to 104 CFU/g of soil). A feasibility study was conducted prior to the full-scale bioremediation study. In this feasibility study, out of six treatments, the application of a bacterial consortium and nutrients resulted in maximum biodegradation of total petroleum hydrocarbon (TPH) in 120 days. Therefore, this treatment was selected for the full-scale study. In the full-scale study, plots A and B were treated with a bacterial consortium and nutrients, which resulted in 92.0 and 89.7% removal of TPH, respectively, in 1 year, compared to 14.0% removal of TPH in the control plot C. In plot A, the alkane fraction of TPH was reduced by 94.2%, the aromatic fraction of TPH was reduced by 91.9%, and NSO (nitrogen-, sulfur-, and oxygen-containing compound) and asphaltene fractions of TPH were reduced by 85.2% in 1 year. Similarly, in plot B the degradation of alkane, aromatic, and NSO plus asphaltene fractions of TPH was 95.1, 94.8, and 63.5%, respectively, in 345 days. However, in plot C, removal of alkane (17.3%), aromatic (12.9%), and NSO plus asphaltene (5.8%) fractions was much less. The population of introduced Acinetobacter baumannii strains in plots A and B was stable even after 1 year. Physical and chemical properties of the soil at the bioremediation site improved significantly in 1 year.

APA, Harvard, Vancouver, ISO, and other styles

42

Góes, Joelmir Da Silva, Andrea Gomes Dellovo, Carla Rocha Sao Mateus, and Guilherme De Oliveira Macedo. "Effect of Polyethylene Terephthalate Tongue Scraper on Oral Levels of Volatile Sulfur Compounds: a randomized clinical trial." Brazilian Dental Science 22, no. 1 (January 31, 2019): Process. http://dx.doi.org/10.14295/bds.2019.v22i1.1671.

Full text

Abstract:

Objective: To evaluate the effect of Polyethylene Terephthalate (PET) tongue scraper on the volatile sulfur compound (VSC) levels. Material and Methods: A randomized, controlled, parallel design was used in this study. Out of the 48 volunteers from Dentistry Department of the Federal University of Sergipe, 40 subjects who met the inclusion criteria were randomly divided into 4 groups (n=10): G1 (control), rinsing of distilled water solution (WS); G2, WS and tongue coating removal (TCR) with toothbrush; G3, WS and TCR with a commercial tongue scraper; and G4, WS and TCR with PET tongue scraper. PET bottles were cut with a rectangular shape (1.0 cm wide x 20 cm long) to obtain PET tongue scraper. The VSC measurements were performed before (T0) and immediately after (T1) each therapy by portable sulfide monitor. Data (ppb) were submitted to Wilcoxon test (α=0.05). The differences between T0 and T1 were calculated and percentage values were assigned. Data (percentage) were submitted to ANOVA and Tukey test (α=0.05). Results: All 40 selected subjects completed the study. All groups reduced significantly the VSC levels after therapy (P<0.01). ANOVA indicated a significant difference among groups (P<0.001). The Tukey test showed that G1 (reduction of 21%) was similar to G2 (31%); G2 was similar to G3 (42%) and different from G4 (52%); G3 and G4 were similar. Conclusion: PET tongue scraper was similar to commercial tongue scraper and provided higher reductions of VSC levels than the toothbrush. KeywordsHalitosis; Polyethylene terephthalates; Sulfur compounds; Tongue.

APA, Harvard, Vancouver, ISO, and other styles

43

Tsai, Wen-Tien, Chien-Hung Hsu, and Yu-Quan Lin. "Highly Porous and Nutrients-Rich Biochar Derived from Dairy Cattle Manure and Its Potential for Removal of Cationic Compound from Water." Agriculture 9, no. 6 (June 2, 2019): 114. http://dx.doi.org/10.3390/agriculture9060114.

Full text

Abstract:

The use of biochar in the horticulture and crop fields is a recent method to improve soil fertility due to its porous features and rich nutrients. In the present study, dairy manure (DM) was used as a biomass precursor in the preparation of highly porous biochar (DM-BC) produced at specific conditions. Based on N2 adsorption-desorption isotherms and scanning electron microscopy (SEM) observations, the resulting biochar featured its microporous/mesoporous textures with a BET surface area of about 300 m2/g and total pore volume of 0.185 cm3/g, which could be a low-cost biosorbent for the effective removal of methylene blue (MB) from the aqueous solution. As observed by the energy dispersive X-ray spectroscopy (EDS), the primary inorganic nutrients on the surface of DM-BC included calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), silicon (Si), sulfur (S), sodium (Na) and aluminum (Al). Furthermore, the resulting biochar was investigated in duplicate for its biosorption performance of cationic compound (i.e., methylene blue, MB) from the aqueous solution with various initial MB concentrations and DM-BC dosages at 25 °C. The findings showed that the biosorption kinetic parameters fitted by the pseudo-second order rate model with high correlations were consistent with its porous features. These experimental results suggested that the porous DM-based biochar could be reused as a biosorbent, biofertilizer, or soil amendments due to the high porosity and the abundance in nutrient minerals.

APA, Harvard, Vancouver, ISO, and other styles

44

Wan, Dongjin, Yang Cao, Yahui Shi, Qi Li, Ying Li, Zhixiang Zhang, Xinze Han, and Yafei Gao. "Construction of heterotrophic-sulfur autotrophic integrated fluidized bed reactor for simultaneous and efficient removal of compound pollution of perchlorate and nitrate in water." Chemosphere 307 (November 2022): 135944. http://dx.doi.org/10.1016/j.chemosphere.2022.135944.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Ahmedzeki, Nada Sadoon, and Ban Jaber Ibrahem. "Reduction of Sulfur Compounds from Petroleum Fraction Using Oxidation-Adsorption Technique." Iraqi Journal of Chemical and Petroleum Engineering 16, no. 1 (March 30, 2015): 35–48. http://dx.doi.org/10.31699/ijcpe.2015.1.4.

Full text

Abstract:

Oxidation of sulfur compounds in fuel followed by an adsorption process were studied using two modes of operation, batch mode and continuous mode (fixed bed). In batch experiment oxidation process of kerosene with sulfur content 2360 ppm was achieved to study the effect of amount of hydrogen peroxide(2.5, 4, 6 and 10) ml at different temperature(40, 60 and 70)°C. Also the effect of amount acetic acid was studied at the optimal conditions of the oxidation step(4ml H2O2 and 60 °C).Besides, the role of acetic acid different temperatures(40, 60, 70) °C and 4ml H2O2, effect of reaction time(5, 30, 60, 120, 300) minutes at temperatures(40,60) °C, 4ml H2O2 and 1 mlHAC) and effect of reaction temperature were studied. The results showed that the percentage removal of sulfur compounds increases with the increasing amount of hydrogen peroxide and amount of acetic acid also the percentage removal of sulfur compounds increases by addition acetic acid, reaction time up to 300 minutes and reaction temperature. In the fixed bed adsorption process, the oxidized kerosene having sulfur content being reduced to 939.28 ppm, was let to flow through a bed of 10Ni/ -Al2O3. The results showed that a sulfur removal of 95.38 % was obtained. By this the total sulfur removal of 98.38 % was obtained from the two consecutive processes. The resultant fuel had only 43.47 ppm. Also a study of the capability of the same bed to desulfurize raw feed of kerosene of 2360 ppm of sulfur compounds was investigated. 43.3% removal of sulfur compounds was achieved which reflects the catalytic properties of the adsorbent which could act as an oxidative adsorptive material. The results showed that by increasing feed flow rate, the breakthrough curve becomes steeper. Also the maximum removal of sulfur compounds was obtained in the case of bed height 20 cm and flow rate 0.3 l/h.

APA, Harvard, Vancouver, ISO, and other styles

46

Qian, Jin, Mingkuan Zhang, Juntao Niu, Xiaoying Fu, Xiangjun Pei, Xing Chang, Li Wei, Rulong Liu, Guang-Hao Chen, and Feng Jiang. "Roles of sulfite and internal recirculation on organic compound removal and the microbial community structure of a sulfur cycle-driven biological wastewater treatment process." Chemosphere 226 (July 2019): 825–33. http://dx.doi.org/10.1016/j.chemosphere.2019.03.139.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Grossman, M. J., M. K. Lee, R. C. Prince, K. K. Garrett, G. N. George, and I. J. Pickering. "Microbial Desulfurization of a Crude Oil Middle-Distillate Fraction: Analysis of the Extent of Sulfur Removal and the Effect of Removal on Remaining Sulfur." Applied and Environmental Microbiology 65, no. 1 (January 1, 1999): 181–88. http://dx.doi.org/10.1128/aem.65.1.181-188.1999.

Full text

Abstract:

ABSTRACT Rhodococcus sp. strain ECRD-1 was evaluated for its ability to desulfurize a 232 to 343°C middle-distillate (diesel range) fraction of Oregon basin (OB) crude oil. OB oil was provided as the sole source of sulfur in batch cultures, and the extent of desulfurization and the chemical fate of the residual sulfur in the oil after treatment were determined. Gas chromatography (GC), flame ionization detection, and GC sulfur chemiluminesce detection analysis were used to qualitatively evaluate the effect ofRhodococcus sp. strain ECRD-1 treatment on the hydrocarbon and sulfur content of the oil, respectively. Total sulfur was determined by combustion of samples and measurement of released sulfur dioxide by infrared absorption. Up to 30% of the total sulfur in the middle distillate cut was removed, and compounds across the entire boiling range of the oil were affected. Sulfur K-edge X-ray absorption-edge spectroscopy was used to examine the chemical state of the sulfur remaining in the treated OB oil. Approximately equal amounts of thiophenic and sulfidic sulfur compounds were removed by ECRD-1 treatment, and over 50% of the sulfur remaining after treatment was in an oxidized form. The presence of partially oxidized sulfur compounds indicates that these compounds were en route to desulfurization. Overall, more than two-thirds of the sulfur had been removed or oxidized by the microbial treatment.

APA, Harvard, Vancouver, ISO, and other styles

48

Jiang, Nan, Fuyong Zhang, and Hua Song. "Effect of reduction temperature on the structure and hydrodesulfurization performance of Na doped Ni2P/MCM-41 catalysts." RSC Advances 9, no. 27 (2019): 15488–94. http://dx.doi.org/10.1039/c9ra01582e.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Metelkin, A. A., O. Yu Sheshukov, M. V. Savel’ev, O. I. Shevchenko, and D. K. Egiazar’yan. "Application of ionic theory to calculate sulfide capacity of slags." Izvestiya. Ferrous Metallurgy 64, no. 2 (April 2, 2021): 104–11. http://dx.doi.org/10.17073/0368-0797-2021-2-104-111.

Full text

Abstract:

The article considers the issues of sulfur removal in the ladle-furnace unit. The sulfur distribution coefficient depends on sulfide capacity of the slag, sulfur activity coefficient, oxidizing potential of the medium and equilibrium constant. The sulfide capacity CS of slags is one of the most important characteristics of refining capacity of the slags used in extra-furnace steel processing. One of the factors affecting the sulfide capacity is temperature. The formula was proposed showing the dependence of sulfide capacity on the optical basicity and temperature, in the temperature range of 1650 – 1400 °C and when the optical basicity Λ is not more than 0.75; the error of the presented formula does not exceed 6 %. The formula for calculating the optical basicity is proposed, which takes into account the influence of basic, acidic oxides and amphoteric oxide Al2O3. It is shown that slags, completely consisting of a homogeneous phase, have an increased optical basicity of aluminum oxide. Heterogeneous slags have a reduced optical basicity of Al2O3 in comparison with homogeneous slags. Perhaps, this fact can be explained by the fact that in homogeneous slags there is a deficiency of the basic oxide CaO and in the conditions under consideration Al2O3 compound begins to exhibit more basic properties than acidic ones, thus, in homogeneous slags, the optical basicity of aluminum oxide is increased and approaches optical basicity of CaO oxide. Calculations carried out on the basis of real heats have shown that with an increase in the content of Al2O3 oxide in the slag, its optical basicity decreases. Known value of the optical basicity makes it possible to determine sulfide capacity of the slag, sulfur distribution coefficient between metal and slag, and, accordingly, final sulfur content in the metal. The research results have shown that it is advisable to apply the ionic theory of slags for the sulfide capacity determination.

APA, Harvard, Vancouver, ISO, and other styles

50

Qiu, Rongchu, J. F. Ferguson, and M. M. Benjamin. "Sequential Anaerobic and Aerobic Treatment of Kraft Pulping Wastes." Water Science and Technology 20, no. 1 (January 1, 1988): 107–20. http://dx.doi.org/10.2166/wst.1988.0014.

Full text

Abstract:

A study of sequential anaerobic and aerobic treatment was conducted with combinations of kraft evaporator condensate (KEC) and caustic extraction (CE) stage bleaching effluent. In addition to conventional measures of treatment efficiency, the transformations and removal of sulfur compounds from the KEC and changes in molecular size fraction of organic carbon and organic chlorine were measured. A large fraction of the BOD in the combined waste could be removed in the anaerobic stage at loadings of up to at least 15 kg COD/m3-d. The overall process produced an effluent with <30 mg/l BOD and SS and with varying amounts of COD, depending on the CE fraction being treated. Fractional removals of organic carbon and COD were approximately equal and were significantly greater than that of organic chlorine. Removal efficiencies were higher for the low molecular weight fraction. One third of the influent sulfur was removed as H2S gas in the anaerobic stage. The remaining sulfur was largely oxidized to sulfate in the aerobic stage, with nearly complete elimination of odors.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Removal of Sulfer compound'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles